A Review: Chill-Block Melt Spin Technique, Theories & Applications

Rapid Solidification Processing (RSP) is an advanced technique for producing new materials. By applying high cooling rates larger than 105 ºC, all thermal and diffusional processes are affected and new phases, new refined structures and new materials are emerged.

Chill-Block Melt Spin (CBMS) technique is the most important rapid solidification process because of its low-costs and flexibility compared to other technologies such as drop tubes and atomization rapid solidification. Mathematical analysis with experiments have revealed that thermal transport is the predominant over momentum transport for ribbon formation and substrate nature and speed control the cooling rates. Microstructural anatomy of the melt-spun ribbons shows a scale-up in the grain size from the wheel side towards the ribbon upper free surface with clear effect of convection-induced instabilities that affect the local cooling rates and microstructures for near Newtonian cooling conditions.

Rapid solidification processing by CBMS tech affects the transport phenomena controlling the phase formation and growth kinetics which lead to the emergence and trapping of new phases in the solid state. These new amorphous, nanostructures and/or microstructures make the new bulk material to have new physical properties differing from those prepared by conventional manners. Many new CBMS materials found their way to the new and advanced applications and replaced also the oldest ones.